How will a seedling grow if it receives no light?

If we look at the matter from the gardener's point of view, however, we can use the rule of thumb that most cultivated plants on sale in seed form prefer to germinate in the dark. There are some notable exceptions however, some greenhouse perennials, epiphytes, many grasses, and even tobacco all prefer light and a large number of seeds are not fussy either way.

The reason is that commercially produced seed is bred and selected for its ease of germination as well as other more obvious characteristics and so peculiarities such as light or dark requirements do not often occur. On the other hand seed which is obtained non-commercially, in small quantities from the home gardener, seed lists, or the more unusual items from seed merchants may prove to be much more fussy in its requirements.